Large caliber smooth bore mortars



Jan. 26, 1960 Filed March 4, 1955 G. BARBE LARGE CALIBER SMOOTH BOREMORTARS 4 Sheets-Sheet 1 /NVENTDR WWW-4:6

' ATTDHNEYS Jan. 26, 1960 G. BARBE LARGE CALIBER SMOOTH BORE MORTARS 4Sheets-Sheet 2 Filed March 4, 1955 INVENTDR ,748 .iznf/ 5v i Arm/wax;

Jan. 26, 1960 BARBE 2,922,338

LARGE CALIBER SMOOTH BORE MORTARS Filed March 4, 1955 4 Sheets-Sheet 5INVEN-TDR .lreayew @r/a ATTUBNEYJ Jan. 26, 1960 G. BARBE LARGE CALIBERSMOOTH BORE MORTARS Filed March 4, 1955 4 Sheets-Sheet 4 INVENTUR 420 2;flaw/e ATTDPINEYV LARGE CALIBER SMOOTH BORE MORTARS Georges Barbe,Paris, France Application March 4, 1955, Serial No. 492,103

Claims priority, application France March 16, 1954 Claims. (Cl. 891) Thepresent invention relates to large caliber smooth bore mortars andespecially mortars for launching antisubmarine projectiles.

Up to this time, such mortars had their barrel rigidly secured to themount supporting the mortar and in view of the limited stress that canbe supported by such a mount, the pressure of the propelling powdergases in the barrel could not exceed a given value (for instance 50 kg.per sq. cm.) which correspondingly limited the range of fire.

The obvious remedy to this drawback would have been to make the barrelmovable for resiliently absorbed recoiling in the mount. The propellinggases pressure could then have been considerably increased withoutunduly stressing the mount. But such recoil systems can be used onlywhen the recoiling unit is sufiiciently heavy to have but a limitedrearward velocity when a projectile is fired. This is the case withguns, the barrels of which must have thick walls and are thereforenecessarily heavy. But mortar barrels require but relatively thin walls(as a rule the ratio of the external diameter to the inner diameterranges from 1.1 to 1.2) and are therefore of insufficient weight tocomply with the above condition and of course it is out of the questionto make them unnecessarily thickwalled and heavy.

Therefore all known large caliber mortars having their barrels rigidlysecured to the mount have a relatively low range.

The object of my invention is to provide a weapon of the above mentionedtype which is free from this drawback.

For this purpose, according to an essential feature of my invention,this weapon includes a plurality of parallel large caliber smooth borebarrels rigid together to form a single recoiling unit slidable in acradle with the interposition of a resilient recoil and counter-recoilmechanism between said unit and said cradle, said barrels being providedwith respective firing means arranged to be operated successively sothat, after all the barrels have been loaded, they can be fired only oneafter the other, and means being provided in said barrels for yieldinglylocking the projectiles therein, whereby, upon one of the barrels beingfired, the projectile or projectiles present in the other barrel orbarrels of the recoiling unit is or are prevented from moving withrespect to said unit, whereas the locking means in the barrel that isbeing fired yield after a short resistance to the propelling action ofthe powder cases therein.

Other features of my invention will become apparent in the followingdetailed description of some specific embodiments thereof with referenceto the accompanying drawings, given merely by way of example and inwhich:

Fig. 1 is an elevational view of the weapon according to my invention infiring position.

Fig. la is a similar view, the weapon being in charging position.

Fig. 2 is a rear view of the Weapon in horizontal position.

2,922,338 Patented Jan. 2 16, 196i) Fig. 3 is a longitudinal sectionalview'of' one of the barrels of the weapon.

Fig. 3a is a separate view of a rod to be used in order to release themeans for yieldingly locking a projectile in a barrel.

The weapon shown by the drawing includes a recoiling unit essentiallyconstituted by four barrels 1 rigidly assembled together and therespective axes of which are located along the edges of a prism ofsquare cross-section.

This recoiling unit is slidable in cradle 3 pivotable in a training base4 about a horizontal axis, for elevating displacements of the barrels.This base 4 is itself pivotable about a vertical axis on a pedestal 5carried by the ship deck 6 for traversing displacements of the barrels.

A resilient recoil and counter-recoil mechanism is interposed betweencradle 3 and the recoiling unit 1. It may be of any suitable, and forinstance conventional, type, including brake and recuperator cylinders Cand C carried by cradle 3, and pistons cooperating with said cylindersand having their rods R and R fixed to the barrels 1 of the recoilingunit.

At its rear end every barrel 1 is surrounded by a sleeve 1a of squareouter section in which a breechblock 10 is movable transversely.Furthermore in this rear end portion of said barrel 1 there is fitted asteel plug 7 forming the combustion chamber and the rear end of which isprovided with a cylindrical bore adapted to receive the powder case 8.The front portion of plug 7 forms an enlarged chamber provided withholes 9 for the passage of the powder gases to the rear part of theprojectile 11.

The projectile 11, the rear end and the tail fins 12 of which arevisible on Fig. 3, is provided, on its rear end face, with a plate 16carrying spindles 13 on which are pivoted about their front ends, arms14 the hooked rear ends of which engage under a mushroom-shapedprojection 15 integral with plug 7. The bent front ends 14a of arms 14are provided with notches engaging on projections 17a of an annularpiece 17 movable axially with respect to plate 16. An annular block 13of a resilient material is interposed between this piece 17 and anotherannular piece 19 slidable axially in piece 17. Piece 19 is intended tobear on the front end face of mushroomshaped projection .15 when theprojectile is forced into the barrel. Thus after the hooked ends of arms14 have engaged under the head of projection 15, resilient block 18tends to expand in the axial direction and tightly holds said hookedends applied against the rear face of the mushroom-shaped part 15,whereby the projectile is resiliently fixed in barrel 1.

When the powder charge is fired, the pressure of the gases quicklyreaches a value suflicient to deform rods 14, thus releasing theprojectile. The short resistance of rods 14 immediately upon firing ofthe charge corresponds to the forcing of the rifling band in a rifledbarrel. Resilient block 18 and rods 14 are carried along by theprojectile.

In piece 17 is screwed a screw-threaded rod 30 extending inside piece19. This rod 30 forms, at the rear end thereof, a short sleeve providedwith a hole of polygonal section. On the other hand, the top end of themushroomshaped projection 15 is provided with an axial hole 31 throughwhich it is possible to engage a rod 31a (Fig. 3a) the end of which isof a polygonal section corresponding to that of the hole provided in therear end of rod'30.

If, for some reason, it is desired to remove a projectile already fixedin the corresponding barrel, I may proceed as follows:

Breech-block 10 being opened, and powder case 8 removed, rod 31a isinserted through hole 31 so that the polygonal end of said rod fits inthe polygonal hole of rod 30. Then rod 31a is rotated about its axis soas to screw rod 30 in piece 17. The front end of rod 30 is thus firstbrought into contact with the rear face of plate16. After this, when rod31a is further rotated, piece 17 is moved rearwardly, thus furthercompressing block 18, and there fore moving the hooked ends of arms 14slightly away from the rear face of mushroom-shaped part 15.Simultaneously, the projections 17a of piece 17 causearms 14 suitabletype, such as known in the art, the switch for controlling ignitionincludes a single operating member 21 capable of occupying fourdiiferent positions in each of which it closes one of the ignitioncircuits 20 of the four barrels respectively.

If ignition is obtained through mechanical means, I may control theclosing of the four breech mechanisms of the four barrels 1 by a singlemember, for instance a rotating disc, capable of occupying four activepositions, in addition to a neutral position. In the first position,this disc closes the breech of the first barrel but leaves the threeother breeches slightly open so that their firing pins cannot strike thecharge primer. In the second position, the first barrel having beenfired, the above mentioned disc closes the second breech mechanism andthe corresponding barrel can be fired, and so on.

Preferably, the four barrels are charged simultaneously. For thispurpose, the weapon is given (Fig. 1a) a suitable negative elevation(for instance 15) where the front portion of the recoiling unit isbearing against a support. The breech mechanisms are opened and thepowder cases introduced in the powder chambers.

During this time, the projectiles are being charged through the barrelnozzles,

A shell elevator has brought a carrier 23, with four projectilesthereon, along rail 23a from a lower position (Fig. 1) under the deck toan upper position shown by Fig. 1a where the four projectiles are inline with the four barrels.

The projectiles are then driven intothe respective barrels by means offour rammers 24 of the chain type. The rammer heads are shown at 25.

When carrier 23 is returned to its lower position of Fig. 1, it can beloaded with projectiles carried by two rotating barrels 26 (best visibleon Fig. 2). For this pur: pose, four projectiles as shown at 11a, 11b,11c and 11d on said two barrels 26 are pushed onto carrier 23 by meansof push members 27.

Fresh projectiles are supplied to barrels 26 by carriers 28 slidablealong vertical rails 29.

In a general manner, while I have, in the above description, disclosedwhat I deem to be practical and efiicient embodiments of my invention,it should be well understood that I do not wish to be limited thereto asthere might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

What I claim is:

l. A mortar which comprises, in combination, a cradle, a plurality ofparallel large caliber smooth bore relatively thin-walled barrelsrigidly assembled together side by side to form a unit slidable in saidcradle in a direction parallel to their axes, a resilient recoil andcounter-recoil mechanism interposed between said cradle and said unit,firing means for said barrels respectively arranged'to be operable onlyseparately so that only one barrel can be fired at a time, and means foryieldingly locking one projectile in each of said barrels to prevent theprojectiles located respectively in barrels that are not being firedfrom moving with respect to said barrels, whereas the locking means ofthe projectile in a barrel that is being fired are arranged to yield tothe pressure developed in said last mentioned barrel, wherebythe inertiaof all said barrels upon the firing of a single shell resists the recoilshock to a substantially greater degree than would a single barrel.

2. A mortar which comprises, in combination, a cradle, four largecaliber smooth bore relatively thin-walled barrels rigidly assembledtogether having their axes located along the edges of a prism thecross-section of which is a square, to form a'unit slidable in saidcradle in a direction parallel to their axes, a recoil and counterrecoilmechanism interposed between said cradle and said unit, firing means forsaid barrels respectively arranged to be operable only separately sothat only one barrel can be fired at a time, and means for yieldinglylocking one projectile in each of said barrels to prevent theprojectiles located respectively in barrels that are not beingfired'frorn moving .with respect'to'said barrels, whereas the lockingmeans of the projectile in a barrel that is being fired are arranged toyield to the pressure developed in said last mentioned barrel, wherebythe inertia of all said barrels upon the firing of a single shellresists the recoil shock to a substantially greater degree than would asingle barrel.

3. A weapon which comprises, in combination, a cradle, a plurality ofparallel large caliber smooth bore barrels rigidly assembled togetherside by side to form v a unit slidable in said cradle in a directionparallel to their axes, a recoil and counter-recoil mechanism interposedbetween said cradle and said unit, a breech mechanism at the rear end ofeach of said barrels for charging powder cases in said last mentionedbarrel from the rear, the front portions of said barrels. being adaptedto with respect to said barrels, whereas the locking means of theprojectile in a barrel that is being fired are arranged to yield to thepressure developed in said last mentioned barrel.

4. A weapon 'which comprises, in combination, a

cradle, four large caliber smooth bore barrels rigidly assembledtogether having their axes located along the edges of a prism thecross-section of which is a square, to form a unit slidable in saidcradle in a direction parallel to their axes, a recoil andcounter-recoil mechanism'in terposed between said cradle and said unit,a breech mechanism at the rear end of each of said barrels for chargingpowder cases in said last mentioned barrel from.

. troduced through the muzzle of said barrels, a steel plug.

in each of said barrels ahead of said breech mechanism and forming acombustion chamber, firing means for said barrels respectively arrangedto be operable only separately so that only one barrel can be fired at atime, and means for yieldingly locking one projectile in each of saidbarrels to prevent the projectiles located respectively in barrels thatare not being fired from moving with respect to said barrels, whereasthe locking means of the projectile in a barrel that is being fired arearranged to yield to the pressure developed in said last mentionedbarrel.

5. A Weapon which comprises, in. combination, a cradle, a plurality ofparallel large caliber smooth bore barrels rigidly assembled togetherside by side to form a unit slidable in said cradle in a directionparallel to their axes, a resilient recoil and counter-recoil mechanisminterposed between said cradle and said unit, firing means for saidbarrels respectively arranged to be operable only separately so thatonly one barrel can be fired at a time, and means for yieldingly lockingone projectile in each of said barrels to prevent the projectileslocated respectively in barrels that are not being fired from movingwith respect to said barrels, whereas the locking means of theprojectile in a barrel that is being fired are arranged to yield to thepressure developed in said last mentioned barrel, said locking meansinc1uding a mushroom-shaped projection carried by said plug at the frontend thereof, a plurality of arms pivoted at their front ends to the rearend of every projectile and having hooked rear ends adapted to engagebehind the head of said mushroom-shaped projection, and resilient meanscarried by said rear end of said projectile so as to be compressed whenthe projectile is forced into the barrel for yieldingly applying saidhooked ends against the rear face of said mushroom projection.

References Cited in the file of this patent UNITED STATES PATENTS

